I will say back on the topic and associated topic of trusting an FB post: I bet that there is a lot of truth to this story because of how airlines are all about on time, on time and on time. But when you see a post so poorly written and the same story told a couple different times in slightly different ways, you get a feeling that the truth is probably somewhere in the middle.
I mean really what are the agents supposed to do about the baggage? Just take it from them because they don't understand that it doesn't fit on the a/c? Then they become the bad guys. The obviously can't let them take the baggage. Yell at them until they just get on the plane without it anyways? I don't think so. Coddle them until the flight is late and the other pax are now delayed and even then the couple might not understand and still have a hard time getting on? That sounds like a lose too. This was not an easy situation for anybody to handle. As it was said before, this is not a bus. You can't just throw people on and let them figure it out amongst themselves.
I think it would have been nice if they had tried to get a hold of some family members and have them talk some sense into the couple or arrange for another person to specifically help these two out, but airlines aren't day cares. I'm sorry, but don't let your parents fly by themselves if they can't understand time. This is as much to blame on the family of this gentleman as it is on the airline. Alaska has done the best to make up for something that really wasn't their fault.